1. Field of the Invention
The present disclosure generally relates to tires, such as automobile tires, and more particularly to a tire adapted for and method of maintaining proper inflation pressure utilizing active materials.
2. Discussion of Prior Art
Properly functioning tires are not only important to ensure the health and safety of the user, but they also play a role in maintaining optimal fuel efficiency. To accomplish both tasks, a proper balance must often be struck, perhaps nowhere is this more widely felt than with respect to inflation pressure. For example, it is appreciated by those of ordinary skill in the art that a hypo-inflated tire may cause too great of a contact patch and excessive stress within the sidewalls, while a hyper-inflated tire may result in an insufficient patch and therefore, insufficient traction. Moreover, hypo-inflation typically contributes to excessive “rolling resistance” (i.e., the tendency for a tire to stop rolling under load) thereby reducing fuel economy.
Concernedly, control of inflation pressure is difficult, as it is also appreciated that many ambient and inherent conditions, including outside temperature, and the stiffness and integrity of the tire material may cause it to fluctuate undesirably. Conventional tires typically provide an air valve whereupon an air pressure gauge may be applied to determine an improper (i.e., excessive or low) inflation pressure. An excessive or low pressure is then manually cured by bleeding off the excess pressure or adding air, respectively. More recently, conventional valve assemblies employing automatic pressure sensors (e.g., TPMs) have been developed to detect and inform a user of an excessive or low pressure condition. However, in these applications, manual modification of air pressure is still required.